--- title: Start Large netlab Topologies in Smaller Batches «... description: netlab release 1.5 introduces batch-based VM startup for large libvirt topologies, solving a common failure where simultaneously booting many VMs starves them... canonical: https://daily.dev/posts/start-large-netlab-topologies-in-smaller-batches-ipspace-net-blog-8zyho1fkk twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Start Large netlab Topologies in Smaller Batches « ipSpace.net blog | daily.dev og:description: netlab release 1.5 introduces batch-based VM startup for large libvirt topologies, solving a common failure where simultaneously booting many VMs starves them... og:url: https://daily.dev/posts/start-large-netlab-topologies-in-smaller-batches-ipspace-net-blog-8zyho1fkk og:image: https://api.daily.dev/og/posts/8zyHo1fkK.png og:image:alt: Start Large netlab Topologies in Smaller Batches « ipSpace.net blog og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Start Large netlab Topologies in Smaller Batches « ipSpace.net blog **[ipSpace.net Blog](https://daily.dev/sources/ipspace)** · 2 min read · 0 upvotes · 0 comments ## Summary netlab release 1.5 introduces batch-based VM startup for large libvirt topologies, solving a common failure where simultaneously booting many VMs starves them of CPU cycles during initialization. Users can set the `defaults.providers.libvirt.batch_size` parameter in the lab topology file or as a CLI argument to `netlab up`. A user reportedly ran nearly 100 Mikrotik routers on a 24-core server using this approach. Upgrade via `pip3 install --upgrade networklab`. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How do I start a large netlab libvirt topology without Vagrant timing out during boot? netlab 1.5 adds a batch startup feature for libvirt-based topologies. Set the `defaults.providers.libvirt.batch_size` parameter in your lab topology file or pass it as a CLI argument to `netlab up`. This splits VMs into equal-sized groups and starts each batch sequentially, preventing CPU starvation that causes Vagrant to time out when too many VMs boot simultaneously. _Engineers running large virtual labs track netlab releases and workarounds like this on daily.dev._ ## Similar posts on daily.dev - [netlab 26.09: Syslog, More DNS, Netmiko « ipSpace.net blog](https://daily.dev/posts/netlab-26-09-syslog-more-dns-netmiko-ipspace-net-blog-7hzbp4smq) · ipSpace.net Blog · 0 upvotes · 0 comments --- Tags: [#devops](https://daily.dev/tags/devops), [#networking](https://daily.dev/tags/networking) [View this post on daily.dev](https://daily.dev/posts/start-large-netlab-topologies-in-smaller-batches-ipspace-net-blog-8zyho1fkk) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Start Large netlab Topologies in Smaller Batches « ipSpace.net blog","url":"https://daily.dev/posts/start-large-netlab-topologies-in-smaller-batches-ipspace-net-blog-8zyho1fkk","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/start-large-netlab-topologies-in-smaller-batches-ipspace-net-blog-8zyho1fkk"},"datePublished":"2026-08-11T08:56:00.162Z","dateModified":"2026-10-14T02:26:23.553Z","description":"netlab release 1.5 introduces batch-based VM startup for large libvirt topologies, solving a common failure where simultaneously booting many VMs starves them...","image":"https://media.daily.dev/image/upload/s--P4t4XyoV--/f_auto/v1722860399/public/Placeholder%2001","thumbnailUrl":"https://media.daily.dev/image/upload/s--P4t4XyoV--/f_auto/v1722860399/public/Placeholder%2001","isAccessibleForFree":true,"articleSection":"ipSpace.net Blog","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"ipSpace.net Blog","logo":"https://media.daily.dev/image/upload/s--xS7E82MT--/f_auto,q_auto/v1786438303/logos/ipspace?_a=BAMAMicg0","url":"https://daily.dev/sources/ipspace"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/start-large-netlab-topologies-in-smaller-batches-ipspace-net-blog-8zyho1fkk","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"devops,networking","timeRequired":"PT2M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"ipSpace.net Blog","item":"https://daily.dev/sources/ipspace"},{"@type":"ListItem","position":3,"name":"Start Large netlab Topologies in Smaller Batches « ipSpace.net blog"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/start-large-netlab-topologies-in-smaller-batches-ipspace-net-blog-8zyho1fkk#faq","mainEntity":[{"@type":"Question","name":"How do I start a large netlab libvirt topology without Vagrant timing out during boot?","acceptedAnswer":{"@type":"Answer","text":"netlab 1.5 adds a batch startup feature for libvirt-based topologies. Set the `defaults.providers.libvirt.batch_size` parameter in your lab topology file or pass it as a CLI argument to `netlab up`. This splits VMs into equal-sized groups and starts each batch sequentially, preventing CPU starvation that causes Vagrant to time out when too many VMs boot simultaneously. Engineers running large virtual labs track netlab releases and workarounds like this on daily.dev."}}]} ```